A New Detection Method of Oral and Oropharyngeal Squamous Cell Carcinoma Based on Multivariate Analysis of Surface Enhanced Raman Spectra of Salivary Exosomes

Abstract

Raman spectroscopy recently proved a tremendous capacity to identify disease-specific markers in various (bio)samples being a non-invasive, rapid, and reliable method for cancer detection. In this study, we first aimed to record vibrational spectra of salivary exosomes isolated from oral and oropharyngeal squamous cell carcinoma patients and healthy controls using surface enhancement Raman spectroscopy (SERS). Then, we assessed this method’s capacity to discriminate between malignant and non-malignant samples by means of principal component–linear discriminant analysis (PC-LDA) and we used area under the receiver operating characteristics with illustration as the area under the curve to measure the power of salivary exosomes SERS spectra analysis to identify cancer presence. The vibrational spectra were collected on a solid plasmonic substrate developed in our group, synthesized using tangential flow filtered and concentrated silver nanoparticles, capable of generating very reproducible spectra for a whole range of bioanalytes. SERS examination identified interesting variations in the vibrational bands assigned to thiocyanate, proteins, and nucleic acids between the saliva of cancer and control groups. Chemometric analysis indicated discrimination sensitivity between the two groups up to 79.3%. The sensitivity is influenced by the spectral interval used for the multivariate analysis, being lower (75.9%) when the full-range spectra were used.

Emerging roles of exosomes in oral diseases progression

“…Based on the analysis of saliva exosomes, SERS exhibits exceptional sensitivity and specificity in distinguishing malignant and normal ones, enabling the early diagnosis of head and neck cancers. 126 Cheng et al introduced a new technique for inductively coupled plasma mass spectrometry, performing excellently in oral exosomes quantitative analysis. 127 They captured exosomes with the CD63 antibody and detected a signal with cholesterol-based rolling circle amplification and gold-nanoparticle-labeled DNA (Fig.…”

Understanding DNA Epigenetics by Means of Raman/SERS Analysis for Cancer Detection

“…Moreover, they allow real-time monitoring of molecular changes, providing insights into the progression of diseases or the response to treatments. Considering these numerous advantages, our research group has achieved remarkable results based on the Raman/SERS technique's ability to distinguish between normal and diseased samples at the molecular level using multivariate analysis tools [23][24][25]. Sample preparation represents a step of ultimate importance in our protocols due to the fact that good-quality probes lead to accurate results.…”